[Intel-gfx] [PATCH] drm/i915: Mark untiled BLT commands as fenced on gen2/3

[Daniel Vetter]

On Fri, Mar 23, 2012 at 08:03:23PM +0100, Daniel Vetter wrote:
> On Wed, Mar 21, 2012 at 10:48:18AM +0000, Chris Wilson wrote:
> > The BLT commands on gen2/3 utilize the fence registers and so we cannot
> > modify any fences for the object whilst those commands are in flight.
> > Currently we marked tiled commands as occupying a fence, but forgot to
> > restrict the untiled commands from preventing a fence being assigned
> > before they were completed.
> > 
> > One side-effect is that we ten have to double check that a fence was
> > allocated for a fenced buffer during move-to-active.
> > 
> > Reported-by: Jiri Slaby <jirislaby at gmail.com>
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=43427
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: stable at kernel.org
> 
> I've had a few comments on irc about a preliminary version of this patch,
> and Chris addressed them all. So
> 
> Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> 
> Futhermore I've stitched together a little testcase in i-g-t, and it
> indeed blows up without this patch. So
> 
> Testcase: i-g-t/tests/gem_tiled_after_untiled_blt
> Tested-by: Daniel Vetter <daniel.vetter at ffwll.ch>

... and now also the report from our QA:

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=47990
-- 
Daniel Vetter
Mail: daniel at ffwll.ch
Mobile: +41 (0)79 365 57 48